Portable electrical transmitter unit for phonographs



Sept. 2s,192 e. 1,601,425

H. H. BRISTOL PORTABLE ELECTRICAL TRANSMITTER UNIT FOR PHONOGRAPHSFiled' May 1, 1926 2 Sheets-Sheet l I INVENTOR.

' HOWARD HLBR'ISTOL.

BY 1' I I A 'TTORNEY Sept. 28 192s. 1,601,425

H. H. BRISTOL PORTABLE ELECTRICAL TRANSMITTER UNIT FDR PHONOGRAPHS FiledMay 1, 1926 2 Sheets-Sheet 2 TINVENTOR. HOWARD H. BRISTOL 'A TTORNEYPatented Sept. 28, 1926.

UNITED j STATES- PATENT OFFICE.

HOWARD H. BRISTOL, F. NAUGATUCK, CONNECTICUT, A SSIGNOR TO THE BRISTOLCOMPANY, OF WATERBUBY, CONNECTICUT, A CORPORATION .OF CONNECTICUT,

roaTaB n ELECTRICAL TRANSMITTER UNIT FOR rnonoe'imrns. I

Application filed m 1, 1926. Serial No. 105,993.

The invention relates to apparatus for 'reproducing sound, moreparticularly to apparatus of the. phonographic or talking machine typeutilizing a rotating record member and a stylus adapted to move .in thegrooves thereof. It has for its object the .provision of electricaltransmitter apparatus of the microphone type and carrying the saidstylus, more especially in the nature 1 of a self-contained unit whichma readily be associated with the record rotating member of aphonograph'and having a movable arm carrying the transmitter memberwhich is actuated by said stylus. A further object of the inventionconslsts in means embodied in said unit whereby, when the transmitter isnot in use, it may be suitably supported and the actuating current fortransmitting the sound vibration at the same time auto- 2 matically cutoff. 7 v

A, still further object of the invention resides in a portable unit ofthe aforesaid type which is compact and so constructed that it will be.stable without permanent attachment and will form a substantial supportfor the movable transmitter carrying arm. This obviates the necessity ofproviding attaching means which would mar to a greater or. less degreethe phonograph with which it is desired-to associate the unit.

The nature of the invention, however, will best be understood whendescribed in connection with the accompanying drawings, in whic hv Fig.1 is a fragmentary side elevation of a phonograph turntable and theassociated unit, together with a loud speaker device operated thereby.

Fig. 2 is a side elevation of the unit with portions broken away; andFig. 3 is a frag- 'mentary front elevation of the unit with transmitterarm cut oil.

Fig. 4: is a fragmentary plan of a turntable and record and a horizontalsection thru the unit associated therewith, and illustrates thetransmitter arm in operative position for playing the record.

Fig. 5"is a fragmentary plan view of the unit with portion of top brokenaway and with transmitter arm in its inoperative position.

Referring to the drawings, 1b designates a supporting table or baseupon. which'is mounted a phonograph turntable 11 as a suitable means forrotating a phonographic record-12 and operated in any suitable andwell-known manner for imparting the proper speed thereto, which recordmay be of the usual disk type shown; With this turntable and record isadapted to be associated the novel and portable transmitter unitheremafter more fully describedand contained with a casing 13 mountedupon a weighted base 14. The underface of the base may be provided witha suitable covering as of felt to insure against scratching or otherwisemarring of the upper surface of the support 10. Said base is providedalso with a plurality of sockets 15 for plugging in, for example, thebattery 16 for operating the transmitter and a loud speaker device orthe like 17. It is understood, of course,

that'usual amplifying means (not shown) may also be included, ifdesired, in the cuit to the speaker device 17 In the cas1ng'13 issuitably mounted to swing in a horizontal plane and a vertical plane anarm 20 carrying at its outer end an electrical transmitter 21 of themicrophone type. The latter is designed to carry cira stylus 22 adaptedto fit in the grooves of the record 12 to actuate thereby the diaphragmof the microphone in manner well understood to produce variations in theelectrical current, but forms no particular part of the presentinvention.

The invention relates more particularlyin the provision of theself-contained port-' able unit comprising the arm 20 with microphone 21attached thereto, the base 14 and casing 13 containing mechanismhereinafter described. For example, the casing 13 will contain asuitable transformer 23, condenser 24 and potentiometer 25, the latterhaving a shaft 26 projecting thru the top of the casing with knob 27thereon for conveniently manipulating same to vary the resistance of theoutgoingcircuit to the speaker device,

the volume of reproduced sound thereof being accordingly varied thereby.A substantial weight 28 is also provided in the bottom of the casing toprevent overbalancing of the same by the arm 20 and attached microphone21 and assures a satisfactory support therefor.

In order forthestylus 22 to readily follow the grooves of the record 12,it will be understood that arm' 20 must have a movement both in ahoriontal plane and in a vertical plane; and to this end, said arm maybe carried by a sleeve 30 fitting over a stud 31 projecting upwardlyfrom the bottom of the casing, said sleeve being vertically positionedby a pin or screw 32'fitting into a groove 33 of the stud. The upper endof sleeve 30, moreover, is bifurcated and the inner end 34 of arm'QQ ispivotally connected thereto. The casing wall, furthermore, is cut awayas at 35 to ermit arm 20 to swing over the desired arc n a horizontalplane. There extends also radially from said casing, as by being fixedlyattached thereto in any suitable manner, a bracket member 36 in theplane of horizontal movement of the arm 20 and having a curved arm 37extending laterally from its end toward arm 20, the same being adaptedto receive the latter when it is at one of its extreme positions, towit-just in advance of its starting position. When thus resting upon arm37, said arm 20 is not intended to function nor the transmitter carriedthereby; and, accordingly, provision is made for automatically cuttingoff the current to the said transmitter lead thereto thru conductors 38.One of these conductors is, therefore, to be opened when the arm 20 isin its inactive position as indicated in Fig. 5 of the drawlngs; and tothis end, there bears upon the periphery of sleeve 30 a brush member 40,whereby when the sleeve is rotated contact will be maintained and themicrophone transmitter allowed to function. However, when sleeve 30 hasmoved to a position in which the arm 20 is substantially over the arm 37of the bracket 36 so that it may rest thereon, an insula-- tion button.or projection 41 also movable with said sleeve enga es with the brush 40to lift same from ma ing contact with the sleeve 30 and thus opens thecircuit at this point. There is little danger, therefore, of leaving theapparatus when not in use in a position which would cause current tocontinue to be consumed and to the detriment of the microphonetransmitter. As soon as arm 20 is a ain moved outwardly, the insulatingpro ection 41 moving with sleeve 30 permits brushAO to again makecontact with the said sleeve, rendering the. transmitter alive and readyfor reproducing sound from the record 12.

eon425 ductors therefrom extending-into the casing for externalconnection, a stationary supporting bracket extending outwardly from thecasing substantially in'the plane of horizontal movement of themicrophone carrying arm and adapted to supportthe latter, and meansmoving with said microphone carrying arm to cut off the actuatingcurrent to its microphone transmitter when the said arm rests on thesaid stationary bracket;

2. An electrical transmitter unit for phonographs, comprising a casing,an arm extending therefrom and swingably mounted therein to oscillate ina horizontal plane and also in a vertical plane, a microphone carried atthe outer end of said arm and conductors therefrom extending into thecasing for external connection, a stationary supporting bracket'extending outwardly from the casing substantially in the plane ofhorizontal movement ofthe microphone carrying arm and adapted tosupportv the latter, means moving with said microphone carrying arm tocut off the actuating current to its microphone transmitter when thesaid arm rests on the said stationary bracket, and a weight in thebottom of said casing to overbalance the moment of the microphone armand microphone transmitter.

3. An electrical transmitter unit for phonographs, comprising a casing,a vertically disposed sleeve mounted for oscillation therein, an armextending. from the casing and movable with the sleeve in a.horizontalplane and also in' a vertical plane, a stationary supporting bracketextending outwardly from the casing substantially in the plane ofhorizontal movement of the said movable arm, a microphone carried at theouter end of said movable arm, and conductors therefrom to said casingfor external connection, a contact brush bearing against said verticallydisposed sleeve and included in circuit with one of the said conductors,an insulation projection on said sleeve, movable therewith in the planeof said brush and adapted to engage and lift the brush off the sleeve tointerrupt the cirand also in a vertical plane, a microphone carried atthe outer end of said arm and conductors therefrom extending into thecasing for external connection, a stationary supporting bracketextending outwardly from the casing substantially in the plane ofhorizontal movement of the. microphone carrying arm and having alaterally extending arm for receiving and supporting said microphonecarrying arm against motion in the vertical plane, and means moving 10with said microphone carrying arm to cut ofi the actuating current toits microphone transmitter when the said arm rests on the said laterallyextending arm.

In testimony whereof I aflix my signature.

HOWARD H. BRISTOL.

